Apps that work with Apple's HealthKit platform have been disappeared from the App Store due to an unspecified bug.
The health and fitness focused HealthKit, one of the headline features of iOS 8, was supposed to be supported by a range of apps when the operating system was released to users on Wednesday. However, Apple has temporarily removed them from its store.
Apple said: "We discovered a bug that prevents us from making HealthKit apps available on iOS 8 today. We're working quickly to have the bug fixed in a software update and have HealthKit apps available by the end of the month."
HealthKit is intended to bring together a range of data on users' health including, for example, calories burned during exercise and heart rate, and collate them in a single dashboard, presented in Apple's Health app.
Third party developers can also use the information, but Apple has laid down a number of rules about what can and can't be done with the sensitive data — for example, apps can't serve advertising against the data or sell it onto other ad companies, though it can be passed on to other third parties, such as health professionals, if the user consents.
The platform has already been getting interest from the healthcare industry. According to recent reports, Apple has held discussions with US healthcare institutions including Mount Sinai, the Cleveland Clinic, and Johns Hopkins, along with electronic health records company Allscripts.
It has also been reported that Apple has been in talks with health insurers including United Health and Humana. Both companies have previously created programs to integrate data gathered from wearable devices into their policies.
Due to the highly personal nature of health data, the system has already attracted questions on its privacy implications: the attorney general of Connecticut earlier this week requested Apple provide more detail on how it intends to make sure third party health apps are respecting users' privacy.
Apple has already stipulated that all HealthKit apps must keep users' data out of iCloud, a move likely made with privacy in mind. The demand isn't surprising given the confidential nature of health data, but follows not long after a number of high profile iCloud accounts were broken into, and personal photos published on the internet.
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